St-Pierre, of Montreal, thoroughly dominated Penn with a grinding, unrelenting ground-and-pound barrage over the last three rounds of their fight on Saturday at UFC 94, in Las Vegas. Although scheduled for five rounds, the fight was stopped after the fourth round on the advice of the ringside doctor.

Penn never managed any meaningful offense. He spent much of the second and almost all of the third and fourth rounds on his back, smothered by St-Pierre, who wore down Penn with a steady stream of strikes that left Penn bruised and bleeding.

Although Penn resisted St-Pierre's wrestling in the first round, the welterweight titlist started scoring takedowns at will in the second round. The French Canadian said he wanted to neutralize the excellent boxing of Penn, UFC's reigning lightweight champion.

"My strategy was in the first two rounds to make a wrestling match with him, because he has very quick hands and his shoulder is made for boxing," St-Pierre said immediately after the bout. "Because he has small shoulders, by making him wrestle, all the blood would have (to) go into his shoulder and it would have become stiff, and his hand would not come out as it is usually."

The matchup was billed as a bout between two of the world's most skilled fighters, with St-Pierre and Penn rated among the top four in several pound-for-pound ranking lists, including those of Sports Illustrated and Yahoo Sports. Online oddsmakers listed St-Pierre as a slight favorite.

St-Pierre (18-2) has won both of his fights against Penn (13-5-1), whom he beat via split decision in March 2006.

Saturday's bout was only for the belt of the welterweight division (170 pounds). St-Pierre said he now views rising star Thiago Alves as the top contender for the welterweight championship.

Machida KOs Silva

On a night filled with bouts decided by judges' scorecards, it took a light-heavyweight fighter known for decision wins to pull off the show's only conclusive finish outside of the main event.

Lyoto Machida kept his perfect record intact with a first-round knockout of previously undefeated Thiago Silva (13-1). Machida (14-0) followed his usual pattern of evading damage, but with Silva coming straight ahead, the eventual winner took advantage of several openings to land combinations and score takedowns against his fellow Brazilian.

Machida knocked down Silva twice with punches in the first four minutes of the contest, but the final shot had the most impact. As the first round came to a close, Machida tripped down Silva as they clinched against the fence and followed it with a downward right hand that knocked Silva unconscious as he lay on the mat, milliseconds before the bell.

Going into Saturday's event, Machida had won four of his five UFC fights via decision.

After the bout, Machida played to the crowd as he clamored for a championship fight in the light-heavyweight division (205 pounds). "People, do I deserve a title shot?" he asked as the audience cheered.

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